Lucas left and did come back
Brooke never forgave Peyton or Lucas
Haley and Nathan are married…they are having problems and Haley went to the train station but didn't leave with Chris. Haley and Nathan are having a lot of problems like in the show and she's on her way back to apartment now to tell Nathan about Chris
Anna and Felix did move to Tree Hill and Anna and Lucas are still 'together' while Brooke and Felix are still benefiting
The whole conflict between Anna and Peyton did happen so they aren't talking
Peyton did go through all the things she's dealt with throughout the second season including the cocaine, but only Anna and Haley know about it. The stuff at the dance happened but she didn't open Tric with Karen and the lesbian thing happened but Brooke hasn't been there for her because they aren't talking.
The whole heart defect thing didn't happen and Jake didn't come back
Other then what I mentioned and things like the slumber party and the other stuff the includes Brooke and Peyton being friends again… I think just about everything in the second season happened.